Technical Field
Embodiments of the present disclosure generally relate to the field of display technologies, and particularly, to a color filter (CF) substrate and a method of manufacturing the same, an organic light emitting display panel, and a display device.
Description of the Related Art
Active matrix organic light emitting diode (AMOLED) panel is applied as a next generation display technology, and has advantages in image quality, efficiency and cost over conventional thin film transistor LCD (TFT-LCD). Specifically, in terms of display efficiency, AMOLED has a quicker response speed, a higher contrast and a wider visual angle. AMOLED has a small amount of electricity consumption, which is only about 60% of that of TFT-LCD. Further, AMOLED has a self luminous property without requiring backlight source, and thus it can be manufactured to be lighter and thinner than TFT-LCD and reduce a cost of a backlight module, which is up to 30˜40% of a production cost of TFT-LCD.
However, the greatest problem presented in AMOLED is yield, and the price of AMOLED is much higher than that of TFT-LCD when manufactured with the current yield, which limits wide application of AMOLED to a large extent.
Currently, a WOLED+CF mode, which is a mode in which color filters (CFs) are used in combination with a white OLED back panel, is utilized to achieve color display by some display manufacturers. As a technological choice of AMOLED, the WOLED+CF mode not only has advantages such as high availability of organic electroluminescence (EL) materials, high aperture ratio, easiness in achieving large screen and the like, but also tends to ensure the yield in mass production.
The WOLED+CF mode is usually achieved in a way that an array back panel and a CF substrate are assembled. A structure of a conventional CF substrate used for LCD display is shown in FIG. 1. During the manufacturing of the CF substrate, generally, firstly a black light shielding region or black matrix (BM) is manufactured, then sub-pixel color filters of three colors of red/green/blue (R/G/B) are manufactured, and finally, post spacers (PS) are manufactured, as supports, at positions corresponding to the BM. Specific process steps of manufacturing the post spacers comprises: coating and patterning a BM material; coating and patterning red, green and blue photoresists; forming an over-coat (OC); and forming PS posts.
However, since a larger assembly thickness is required in the WOLED+CF implementation of AMOLED, it is required that the PS posts, as supports, in the CF substrate have a larger height, which is very difficult to be implemented in process, results in much complicated process implementation steps, and cannot ensure yield. Moreover, such PS structures will be easily damaged during the assembly with the OLED back panel, thereby resulting in reduction in overall yield of AMOLED.